Paint compositions for high infra-red reflectivity with a low gloss property

Abstract

The present invention relates to paint compositions which provide a Chemical Agent Resitant Coating (CARC), consisting of one layer topcoat paint system, which imparts an increase in the reflectivity at the thermal infra-red region, while controlling the colour in the visible range and are maintaining a low gloss, comprising: an extender selected from polyolefins and substituted polyolefins; a pigment, selected from a metal oxide calcined at a temperature of above 600 DEG C. and a paste of metal flakes and any mixture thereof; a binder consisting of a modified polyurethane resulted from an isocyanate and a co-reactant possessing at least two hydroxy groups, and a solvent system to dissolve the components in the paint composition.

We claim: 
     
       1. Paint compositions providing a Chemical Agent Resistant Coating (CARC), consisting of one layer topcoat paint system, which imparts an increase in the reflectivity at the thermal infra-red region, while controlling the colour in the visible range and are maintaining a low gloss, which comprise: an extender selected from polyolefins and substituted polyolefins, in an amount of from 3 to 7% by weight of the composition;   a pigment selected from a metal oxide calcined at a temperature of above 600° C., in an amount of from 30 to 50% by weight of the composition, a paste of metal flakes, in an amount of from about 12 to 30% by weight of the composition, and any mixture thereof;   a binder, and   a solvent system to dissolve the components in the paint compositions, wherein the binder used is a particular modified polyurethane produced by the reaction of (i) an isocyanate and (ii) a co-reactant possessing at least two hydroxy groups and being selected from the group consisting of acrylics, epoxies and polyesters, in an amount of from 20 to 55% by weight of the composition.     
     
     
       2. The paint compositions according to claim 1, wherein the metal in said pigment is selected from the group consisting of cobalt, aluminum, nickel, copper and zinc, and any mixture thereof. 
     
     
       3. The paint compositions according to claim 1 wherein said metal oxide has a particle size below 325 mesh. 
     
     
       4. The paint compositions according to claim 1, wherein said paste comprises the metal flakes in a volatile hydrocarbon. 
     
     
       5. The paint compositions according to claim 4, wherein said volatile hydrocarbon is a mineral spirit. 
     
     
       6. The paint compositions according to claim 1, wherein said solvent system to dissolve the components in the paint compositions, is a volatile aromatic hydrocarbon. 
     
     
       7. The paint compositions according to claim 1, wherein the isocyanate prepolymer in said binder is a slurry consisting of a mixture of xylene-butyl acetate, having a solid content of 70% by weight.